1. Field of the Invention
This invention relates to a light emitting device that guides and radiates an emission light of a light emitting element in a predetermined direction.
2. Description of the Related Art
Heretofore, a light emitting device is known, that has a plurality of light emitting diodes. In recent years, the application of the light emitting diode is enlarged, this the light emitting diode is widely used for indoor lighting, radiation of object in a scanner and the like. The above-mentioned light emitting device that needs a large amount of light includes a light emitting device to which heat radiation measures are applied for preventing thermal destruction of the light emitting diode itself due to heat generated in the light emitting diode (for example, refer to JP-2011-9789 A1).
A solid element device described in JP-2011-9789 A1 has a configuration that a heat radiation pattern is formed in a rear side of an inorganic material substrate in which a light emitting diode element is mounted in a front side, so that heat generated in the light emitting diode element is thermally-conducted from the heat radiation pattern to a heatsink or the like.
However, depending on the configuration of the light emitting device, it may be difficult to bring the heatsink into contact with the heat radiation pattern directly. In addition, in case that the inorganic material substrate is mounted on the mounting substrate in which the circuit pattern for providing electric power to the light emitting diode element is formed, it is needed to form though holes in the mounting substrate for the purpose of bringing the heat radiation pattern into contact with the heatsink, and to bring the heat radiation pattern into contact with the heatsink via the though holes. Consequently, there is a problem that the structure becomes complex and assembly man-hour is increased.